/* [argparse.c wk 17.06.97] Argument Parser for option handling
 * Copyright (C) 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007,
 *               2008, 2010, 2012 Free Software Foundation, Inc.
 *
 * This file is part of GnuPG.
 *
 * GnuPG is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * GnuPG is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>

#include "util.h"
#include "i18n.h"


/*********************************
 * @Summary arg_parse
 *  #include <wk/lib.h>
 *
 *  typedef struct {
 *	char *argc;		  pointer to argc (value subject to change)
 *	char ***argv;		  pointer to argv (value subject to change)
 *	unsigned flags; 	  Global flags (DO NOT CHANGE)
 *	int err;		  print error about last option
 *				  1 = warning, 2 = abort
 *	int r_opt;		  return option
 *	int r_type;		  type of return value (0 = no argument found)
 *	union {
 *	    int   ret_int;
 *	    long  ret_long
 *	    ulong ret_ulong;
 *	    char *ret_str;
 *	} r;			  Return values
 *	struct {
 *	    int idx;
 *	    const char *last;
 *	    void *aliases;
 *	} internal;		  DO NOT CHANGE
 *  } ARGPARSE_ARGS;
 *
 *  typedef struct {
 *	int	    short_opt;
 *	const char *long_opt;
 *	unsigned flags;
 *  } ARGPARSE_OPTS;
 *
 *  int arg_parse( ARGPARSE_ARGS *arg, ARGPARSE_OPTS *opts );
 *
 * @Description
 *  This is my replacement for getopt(). See the example for a typical usage.
 *  Global flags are:
 *     Bit 0 : Do not remove options form argv
 *     Bit 1 : Do not stop at last option but return other args
 *	       with r_opt set to -1.
 *     Bit 2 : Assume options and real args are mixed.
 *     Bit 3 : Do not use -- to stop option processing.
 *     Bit 4 : Do not skip the first arg.
 *     Bit 5 : allow usage of long option with only one dash
 *     Bit 6 : ignore --version and --help
 *     all other bits must be set to zero, this value is modified by the
 *     function, so assume this is write only.
 *  Local flags (for each option):
 *     Bit 2-0 : 0 = does not take an argument
 *		 1 = takes int argument
 *		 2 = takes string argument
 *		 3 = takes long argument
 *		 4 = takes ulong argument
 *     Bit 3 : argument is optional (r_type will the be set to 0)
 *     Bit 4 : allow 0x etc. prefixed values.
 *     Bit 7 : this is a command and not an option
 *  You stop the option processing by setting opts to NULL, the function will
 *  then return 0.
 * @Return Value
 *   Returns the args.r_opt or 0 if ready
 *   r_opt may be -2/-7 to indicate an unknown option/command.
 * @See Also
 *   ArgExpand
 * @Notes
 *  You do not need to process the options 'h', '--help' or '--version'
 *  because this function includes standard help processing; but if you
 *  specify '-h', '--help' or '--version' you have to do it yourself.
 *  The option '--' stops argument processing; if bit 1 is set the function
 *  continues to return normal arguments.
 *  To process float args or unsigned args you must use a string args and do
 *  the conversion yourself.
 * @Example
 *
 *     ARGPARSE_OPTS opts[] = {
 *     { 'v', "verbose",   0 },
 *     { 'd', "debug",     0 },
 *     { 'o', "output",    2 },
 *     { 'c', "cross-ref", 2|8 },
 *     { 'm', "my-option", 1|8 },
 *     { 500, "have-no-short-option-for-this-long-option", 0 },
 *     {0} };
 *     ARGPARSE_ARGS pargs = { &argc, &argv, 0 }
 *
 *     while( ArgParse( &pargs, &opts) ) {
 *	   switch( pargs.r_opt ) {
 *	     case 'v': opt.verbose++; break;
 *	     case 'd': opt.debug++; break;
 *	     case 'o': opt.outfile = pargs.r.ret_str; break;
 *	     case 'c': opt.crf = pargs.r_type? pargs.r.ret_str:"a.crf"; break;
 *	     case 'm': opt.myopt = pargs.r_type? pargs.r.ret_int : 1; break;
 *	     case 500: opt.a_long_one++;  break
 *	     default : pargs.err = 1; break; -- force warning output --
 *	   }
 *     }
 *     if( argc > 1 )
 *	   log_fatal( "Too many args");
 *
 */

typedef struct alias_def_s *ALIAS_DEF;
struct alias_def_s {
    ALIAS_DEF next;
    char *name;   /* malloced buffer with name, \0, value */
    const char *value; /* ptr into name */
};

/* Object to store the names for the --ignore-invalid-option option.
   This is a simple linked list.  */
typedef struct iio_item_def_s *IIO_ITEM_DEF;
struct iio_item_def_s
{
  IIO_ITEM_DEF next;
  char name[1];      /* String with the long option name.  */
};

static int  set_opt_arg(ARGPARSE_ARGS *arg, unsigned flags, char *s);
static void show_help(ARGPARSE_OPTS *opts, unsigned flags);
static void show_version(void);

static void
initialize( ARGPARSE_ARGS *arg, const char *filename, unsigned *lineno )
{
    if( !(arg->flags & (1<<15)) ) { /* initialize this instance */
	arg->internal.idx = 0;
	arg->internal.last = NULL;
	arg->internal.inarg = 0;
	arg->internal.stopped = 0;
	arg->internal.aliases = NULL;
	arg->internal.cur_alias = NULL;
	arg->internal.iio_list = NULL;
	arg->err = 0;
	arg->flags |= 1<<15; /* mark initialized */
	if( *arg->argc < 0 )
	    log_bug("Invalid argument for ArgParse\n");
    }


    if( arg->err ) { /* last option was erroneous */

	if( filename ) {
	    if( arg->r_opt == -6 )
	      log_error("%s:%u: argument not expected\n", filename, *lineno );
	    else if( arg->r_opt == -5 )
	      log_error("%s:%u: read error\n", filename, *lineno );
	    else if( arg->r_opt == -4 )
	      log_error("%s:%u: keyword too long\n", filename, *lineno );
	    else if( arg->r_opt == -3 )
	      log_error("%s:%u: missing argument\n", filename, *lineno );
	    else if( arg->r_opt == -7 )
	      log_error("%s:%u: invalid command\n", filename, *lineno );
	    else if( arg->r_opt == -10 )
	      log_error("%s:%u: invalid alias definition\n",filename,*lineno);
	    else
	      log_error("%s:%u: invalid option\n", filename, *lineno );
	}
	else {
	    if( arg->r_opt == -3 )
	      log_error("Missing argument for option \"%.50s\"\n",
			arg->internal.last? arg->internal.last:"[??]" );
	    else if( arg->r_opt == -6 )
	      log_error("Option \"%.50s\" does not expect an argument\n",
			arg->internal.last? arg->internal.last:"[??]" );
	    else if( arg->r_opt == -7 )
	      log_error("Invalid command \"%.50s\"\n",
			arg->internal.last? arg->internal.last:"[??]" );
	    else if( arg->r_opt == -8 )
	      log_error("Option \"%.50s\" is ambiguous\n",
			arg->internal.last? arg->internal.last:"[??]" );
	    else if( arg->r_opt == -9 )
	      log_error("Command \"%.50s\" is ambiguous\n",
			arg->internal.last? arg->internal.last:"[??]" );
	    else
	      log_error("Invalid option \"%.50s\"\n",
			arg->internal.last? arg->internal.last:"[??]" );
	}
	if( arg->err != 1 || arg->r_opt == -5 )
	    exit(2);
	arg->err = 0;
    }

    /* clearout the return value union */
    arg->r.ret_str = NULL;
    arg->r.ret_long= 0;
}


static void
store_alias( ARGPARSE_ARGS *arg, char *name, char *value )
{
    /* TODO: replace this dummy function with a rea one
     * and fix the probelms IRIX has with (ALIAS_DEV)arg..
     * used as lvalue
     */
#if 0
    ALIAS_DEF a = xmalloc( sizeof *a );
    a->name = name;
    a->value = value;
    a->next = (ALIAS_DEF)arg->internal.aliases;
    (ALIAS_DEF)arg->internal.aliases = a;
#endif
}


/* Return true if KEYWORD is in the ignore-invalid-option list.  */
static int
ignore_invalid_option_p (ARGPARSE_ARGS *arg, const char *keyword)
{
  IIO_ITEM_DEF item = arg->internal.iio_list;

  for (; item; item = item->next)
    if (!strcmp (item->name, keyword))
      return 1;
  return 0;
}


/* Add the keywords up to the next LF to the list of to be ignored
   options.  After returning FP will either be at EOF or the next
   character read wll be the first of a new line.  */
static void
ignore_invalid_option_add (ARGPARSE_ARGS *arg, FILE *fp)
{
  IIO_ITEM_DEF item;
  int c;
  char name[100];
  int namelen = 0;
  int ready = 0;
  enum { skipWS, collectNAME, skipNAME, addNAME} state = skipWS;

  while (!ready)
    {
      c = getc (fp);
      if (c == '\n')
        ready = 1;
      else if (c == EOF)
        {
          c = '\n';
          ready = 1;
        }
    again:
      switch (state)
        {
        case skipWS:
          if (!isascii (c) || !isspace(c))
            {
              namelen = 0;
              state = collectNAME;
              goto again;
            }
          break;

        case collectNAME:
          if (isspace (c))
            {
              state = addNAME;
              goto again;
            }
          else if (namelen < DIM(name)-1)
            name[namelen++] = c;
          else /* Too long.  */
            state = skipNAME;
          break;

        case skipNAME:
          if (isspace (c))
            {
              state = skipWS;
              goto again;
            }
          break;

        case addNAME:
          name[namelen] = 0;
          if (!ignore_invalid_option_p (arg, name))
            {
              item = xmalloc (sizeof *item + namelen);
              strcpy (item->name, name);
              item->next = (IIO_ITEM_DEF)arg->internal.iio_list;
              arg->internal.iio_list = item;
            }
          state = skipWS;
          goto again;
        }
    }
}


/* Clear the entire ignore-invalid-option list.  */
static void
ignore_invalid_option_clear (ARGPARSE_ARGS *arg)
{
  IIO_ITEM_DEF item, tmpitem;

  for (item = arg->internal.iio_list; item; item = tmpitem)
    {
      tmpitem = item->next;
      xfree (item);
    }
  arg->internal.iio_list = NULL;
}

/****************
 * Get options from a file.
 * Lines starting with '#' are comment lines.
 * Syntax is simply a keyword and the argument.
 * Valid keywords are all keywords from the long_opt list without
 * the leading dashes. The special keywords "help", "warranty" and "version"
 * are not valid here.
 * The special keyword "alias" may be used to store alias definitions,
 * which are later expanded like long options.
 * Caller must free returned strings.
 * If called with FP set to NULL command line args are parse instead.
 *
 * Q: Should we allow the syntax
 *     keyword = value
 *    and accept for boolean options a value of 1/0, yes/no or true/false?
 * Note: Abbreviation of options is here not allowed.
 */
int
optfile_parse( FILE *fp, const char *filename, unsigned *lineno,
	       ARGPARSE_ARGS *arg, ARGPARSE_OPTS *opts)
{
    int state, i, c;
    int idx=0;
    char keyword[100];
    char *buffer = NULL;
    size_t buflen = 0;
    int inverse=0;
    int in_alias=0;

    if( !fp ) /* same as arg_parse() in this case */
	return arg_parse( arg, opts );

    initialize( arg, filename, lineno );

    /* find the next keyword */
    state = i = 0;
    for(;;) {
	c=getc(fp);
	if( c == '\n' || c== EOF ) {
	    if( c != EOF )
		++*lineno;
	    if( state == -1 )
		break;
	    else if( state == 2 ) {
		keyword[i] = 0;
		for(i=0; opts[i].short_opt; i++ )
		    if( opts[i].long_opt && !strcmp( opts[i].long_opt, keyword) )
			break;
		idx = i;
		arg->r_opt = opts[idx].short_opt;
		if( inverse ) /* this does not have an effect, hmmm */
		    arg->r_opt = -arg->r_opt;
		if( !opts[idx].short_opt ) { /* unknown command/option */
                    if (!strcmp (keyword, "ignore-invalid-option")) {
                        /* No argument - ignore this meta option.  */
                        state = i = 0;
                        continue;
                    }
                    else if (ignore_invalid_option_p (arg, keyword)) {
                        /* This invalid option is in the iio list.  */
                        state = i = 0;
                        continue;
                    }
		    arg->r_opt = (opts[idx].flags & 256)? -7:-2;
                }
		else if( !(opts[idx].flags & 7) ) /* does not take an arg */
		    arg->r_type = 0;	       /* okay */
		else if( (opts[idx].flags & 8) )  /* argument is optional */
                    arg->r_type = 0;	       /* okay */
		else			       /* required argument */
		    arg->r_opt = -3;	       /* error */

		break;
	    }
	    else if( state == 3 ) {	       /* no argument found */
		if( in_alias )
		    arg->r_opt = -3;	       /* error */
		else if( !(opts[idx].flags & 7) ) /* does not take an arg */
		    arg->r_type = 0;	       /* okay */
		else if( (opts[idx].flags & 8) )  /* no optional argument */
		    arg->r_type = 0;	       /* okay */
		else			       /* no required argument */
		    arg->r_opt = -3;	       /* error */
		break;
	    }
	    else if( state == 4 ) {	/* have an argument */
		if( in_alias ) {
		    if( !buffer )
			arg->r_opt = -6;
		    else {
			char *p;

			buffer[i] = 0;
			p = strpbrk( buffer, " \t" );
			if( p ) {
			    *p++ = 0;
			    trim_spaces( p );
			}
			if( !p || !*p ) {
			    xfree( buffer );
			    arg->r_opt = -10;
			}
			else {
			    store_alias( arg, buffer, p );
			}
		    }
		}
		else if( !(opts[idx].flags & 7) )  /* does not take an arg */
		    arg->r_opt = -6;	    /* error */
		else {
		    char *p;
		    if( !buffer ) {
			keyword[i] = 0;
			buffer = xstrdup(keyword);
		    }
		    else
			buffer[i] = 0;

		    trim_spaces( buffer );
		    p = buffer;
		    /* remove quotes if they totally enclose the
                       string, and do not occur within the string */
		    if( *p == '"' && p[strlen(p)-1]=='"') {
		        char *p2=p;

			while(*(++p2))
			  if(*p2=='"')
			    break;

			if(*p2=='"' && *(p2+1)=='\0') {
			  p[strlen(p)-1] = 0;
			  p++;
			}
		    }
		    if( !set_opt_arg(arg, opts[idx].flags, p) )
			xfree(buffer);
		}
		break;
	    }
	    else if( c == EOF ) {
                ignore_invalid_option_clear (arg);
		if( ferror(fp) )
		    arg->r_opt = -5;   /* read error */
		else
		    arg->r_opt = 0;    /* eof */
		break;
	    }
	    state = 0;
	    i = 0;
	}
	else if( state == -1 )
	    ; /* skip */
	else if( !state && isspace(c) )
	    ; /* skip leading white space */
	else if( !state && c == '#' )
	    state = 1;	/* start of a comment */
	else if( state == 1 )
	    ; /* skip comments */
	else if( state == 2 && isspace(c) ) {
	    keyword[i] = 0;
	    for(i=0; opts[i].short_opt; i++ )
		if( opts[i].long_opt && !strcmp( opts[i].long_opt, keyword) )
		    break;
	    idx = i;
	    arg->r_opt = opts[idx].short_opt;
	    if( !opts[idx].short_opt ) {
		if( !strcmp( keyword, "alias" ) ) {
		    in_alias = 1;
		    state = 3;
		}
                else if (!strcmp (keyword, "ignore-invalid-option")) {
                    ignore_invalid_option_add (arg, fp);
                    state = i = 0;
                    ++*lineno;
                }
                else if (ignore_invalid_option_p (arg, keyword))
                    state = 1; /* Process like a comment.  */
		else {
		    arg->r_opt = (opts[idx].flags & 256)? -7:-2;
		    state = -1;        /* skip rest of line and leave */
		}
	    }
	    else
		state = 3;
	}
	else if( state == 3 ) { /* skip leading spaces of the argument */
	    if( !isspace(c) ) {
		i = 0;
		keyword[i++] = c;
		state = 4;
	    }
	}
	else if( state == 4 ) { /* collect the argument */
	    if( buffer ) {
		if( i < buflen-1 )
		    buffer[i++] = c;
		else {
		    buflen += 50;
		    buffer = xrealloc(buffer, buflen);
		    buffer[i++] = c;
		}
	    }
	    else if( i < DIM(keyword)-1 )
		keyword[i++] = c;
	    else {
		buflen = DIM(keyword)+50;
		buffer = xmalloc(buflen);
		memcpy(buffer, keyword, i);
		buffer[i++] = c;
	    }
	}
	else if( i >= DIM(keyword)-1 ) {
	    arg->r_opt = -4;   /* keyword to long */
	    state = -1;        /* skip rest of line and leave */
	}
	else {
	    keyword[i++] = c;
	    state = 2;
	}
    }

    return arg->r_opt;
}



static int
find_long_option( ARGPARSE_ARGS *arg,
		  ARGPARSE_OPTS *opts, const char *keyword )
{
    int i;
    size_t n;

    /* Would be better if we can do a binary search, but it is not
       possible to reorder our option table because we would mess
       up our help strings - What we can do is: Build a nice option
       lookup table wehn this function is first invoked */
    if( !*keyword )
	return -1;
    for(i=0; opts[i].short_opt; i++ )
	if( opts[i].long_opt && !strcmp( opts[i].long_opt, keyword) )
	    return i;
#if 0
    {
	ALIAS_DEF a;
	/* see whether it is an alias */
	for( a = args->internal.aliases; a; a = a->next ) {
	    if( !strcmp( a->name, keyword) ) {
		/* todo: must parse the alias here */
		args->internal.cur_alias = a;
		return -3; /* alias available */
	    }
	}
    }
#endif
    /* not found, see whether it is an abbreviation */
    /* aliases may not be abbreviated */
    n = strlen( keyword );
    for(i=0; opts[i].short_opt; i++ ) {
	if( opts[i].long_opt && !strncmp( opts[i].long_opt, keyword, n ) ) {
	    int j;
	    for(j=i+1; opts[j].short_opt; j++ ) {
		if( opts[j].long_opt
		    && !strncmp( opts[j].long_opt, keyword, n ) )
		    return -2;	/* abbreviation is ambiguous */
	    }
	    return i;
	}
    }
    return -1;
}

int
arg_parse( ARGPARSE_ARGS *arg, ARGPARSE_OPTS *opts)
{
    int idx;
    int argc;
    char **argv;
    char *s, *s2;
    int i;

    initialize( arg, NULL, NULL );
    argc = *arg->argc;
    argv = *arg->argv;
    idx = arg->internal.idx;

    if( !idx && argc && !(arg->flags & (1<<4)) ) { /* skip the first entry */
	argc--; argv++; idx++;
    }

  next_one:
    if( !argc ) { /* no more args */
	arg->r_opt = 0;
	goto leave; /* ready */
    }

    s = *argv;
    arg->internal.last = s;

    if( arg->internal.stopped && (arg->flags & (1<<1)) ) {
	arg->r_opt = -1;  /* not an option but a argument */
	arg->r_type = 2;
	arg->r.ret_str = s;
	argc--; argv++; idx++; /* set to next one */
    }
    else if( arg->internal.stopped ) { /* ready */
	arg->r_opt = 0;
	goto leave;
    }
    else if( *s == '-' && s[1] == '-' ) { /* long option */
	char *argpos;

	arg->internal.inarg = 0;
	if( !s[2] && !(arg->flags & (1<<3)) ) { /* stop option processing */
	    arg->internal.stopped = 1;
	    argc--; argv++; idx++;
	    goto next_one;
	}

	argpos = strchr( s+2, '=' );
	if( argpos )
	    *argpos = 0;
	i = find_long_option( arg, opts, s+2 );
	if( argpos )
	    *argpos = '=';

	if( i < 0 && !strcmp( "help", s+2) ) {
	    if( !(arg->flags & (1<<6)) ) {
		show_help(opts, arg->flags);
	    }
	}
	else if( i < 0 && !strcmp( "version", s+2) ) {
	    if( !(arg->flags & (1<<6)) ) {
		show_version();
		exit(0);
	    }
	}
	else if( i < 0 && !strcmp( "warranty", s+2) ) {
	    puts( strusage(16) );
	    exit(0);
	}
	else if( i < 0 && !strcmp( "dump-options", s+2) ) {
	    for(i=0; opts[i].short_opt; i++ ) {
		if( opts[i].long_opt )
		    printf( "--%s\n", opts[i].long_opt );
	    }
	    fputs("--dump-options\n--help\n--version\n--warranty\n", stdout );
	    exit(0);
	}

	if( i == -2 ) /* ambiguous option */
	    arg->r_opt = -8;
	else if( i == -1 ) {
	    arg->r_opt = -2;
	    arg->r.ret_str = s+2;
	}
	else
	    arg->r_opt = opts[i].short_opt;
	if( i < 0 )
	    ;
	else if( (opts[i].flags & 7) ) {
	    if( argpos ) {
		s2 = argpos+1;
		if( !*s2 )
		    s2 = NULL;
	    }
	    else
		s2 = argv[1];
	    if( !s2 && (opts[i].flags & 8) ) { /* no argument but it is okay*/
		arg->r_type = 0;	       /* because it is optional */
	    }
	    else if( !s2 ) {
		arg->r_opt = -3; /* missing argument */
	    }
	    else if( !argpos && *s2 == '-' && (opts[i].flags & 8) ) {
		/* the argument is optional and the next seems to be
		 * an option. We do not check this possible option
		 * but assume no argument */
		arg->r_type = 0;
	    }
	    else {
		set_opt_arg(arg, opts[i].flags, s2);
		if( !argpos ) {
		    argc--; argv++; idx++; /* skip one */
		}
	    }
	}
	else { /* does not take an argument */
	    if( argpos )
		arg->r_type = -6; /* argument not expected */
	    else
		arg->r_type = 0;
	}
	argc--; argv++; idx++; /* set to next one */
    }
    else if( (*s == '-' && s[1]) || arg->internal.inarg ) { /* short option */
	int dash_kludge = 0;
	i = 0;
	if( !arg->internal.inarg ) {
	    arg->internal.inarg++;
	    if( arg->flags & (1<<5) ) {
		for(i=0; opts[i].short_opt; i++ )
		    if( opts[i].long_opt && !strcmp( opts[i].long_opt, s+1)) {
			dash_kludge=1;
			break;
		    }
	    }
	}
	s += arg->internal.inarg;

	if( !dash_kludge ) {
	    for(i=0; opts[i].short_opt; i++ )
		if( opts[i].short_opt == *s )
		    break;
	}

	if( !opts[i].short_opt && ( *s == 'h' || *s == '?' ) ) {
	    if( !(arg->flags & (1<<6)) ) {
		show_help(opts, arg->flags);
	    }
	}

	arg->r_opt = opts[i].short_opt;
	if( !opts[i].short_opt ) {
	    arg->r_opt = (opts[i].flags & 256)? -7:-2;
	    arg->internal.inarg++; /* point to the next arg */
	    arg->r.ret_str = s;
	}
	else if( (opts[i].flags & 7) ) {
	    if( s[1] && !dash_kludge ) {
		s2 = s+1;
		set_opt_arg(arg, opts[i].flags, s2);
	    }
	    else {
		s2 = argv[1];
		if( !s2 && (opts[i].flags & 8) ) { /* no argument but it is okay*/
		    arg->r_type = 0;		   /* because it is optional */
		}
		else if( !s2 ) {
		    arg->r_opt = -3; /* missing argument */
		}
		else if( *s2 == '-' && s2[1] && (opts[i].flags & 8) ) {
		    /* the argument is optional and the next seems to be
		     * an option. We do not check this possible option
		     * but assume no argument */
		    arg->r_type = 0;
		}
		else {
		    set_opt_arg(arg, opts[i].flags, s2);
		    argc--; argv++; idx++; /* skip one */
		}
	    }
	    s = "x"; /* so that !s[1] yields false */
	}
	else { /* does not take an argument */
	    arg->r_type = 0;
	    arg->internal.inarg++; /* point to the next arg */
	}
	if( !s[1] || dash_kludge ) { /* no more concatenated short options */
	    arg->internal.inarg = 0;
	    argc--; argv++; idx++;
	}
    }
    else if( arg->flags & (1<<2) ) {
	arg->r_opt = -1;  /* not an option but a argument */
	arg->r_type = 2;
	arg->r.ret_str = s;
	argc--; argv++; idx++; /* set to next one */
    }
    else {
	arg->internal.stopped = 1; /* stop option processing */
	goto next_one;
    }

  leave:
    *arg->argc = argc;
    *arg->argv = argv;
    arg->internal.idx = idx;
    return arg->r_opt;
}



static int
set_opt_arg(ARGPARSE_ARGS *arg, unsigned flags, char *s)
{
    int base = (flags & 16)? 0 : 10;

    switch( arg->r_type = (flags & 7) ) {
      case 1: /* takes int argument */
	arg->r.ret_int = (int)strtol(s,NULL,base);
	return 0;
      case 3: /* takes long argument   */
	arg->r.ret_long= strtol(s,NULL,base);
	return 0;
      case 4: /* takes ulong argument  */
	arg->r.ret_ulong= strtoul(s,NULL,base);
	return 0;
      case 2: /* takes string argument */
      default:
	arg->r.ret_str = s;
	return 1;
    }
}


static size_t
long_opt_strlen( ARGPARSE_OPTS *o )
{
    size_t n = strlen(o->long_opt);

    if( o->description && *o->description == '|' ) {
	const char *s;

	s=o->description+1;
	if( *s != '=' )
	    n++;
	for(; *s && *s != '|'; s++ )
	    n++;
    }
    return n;
}

/****************
 * Print formatted help. The description string has some special
 * meanings:
 *  - A description string which is "@" suppresses help output for
 *    this option
 *  - a description,ine which starts with a '@' and is followed by
 *    any other characters is printed as is; this may be used for examples
 *    ans such.
 *  - A description which starts with a '|' outputs the string between this
 *    bar and the next one as arguments of the long option.
 */
static void
show_help( ARGPARSE_OPTS *opts, unsigned flags )
{
    const char *s;

    show_version();
    putchar('\n');
    s = strusage(41);
    puts(s);
    if( opts[0].description ) { /* auto format the option description */
	int i,j, indent;
	/* get max. length of long options */
	for(i=indent=0; opts[i].short_opt; i++ ) {
	    if( opts[i].long_opt )
		if( !opts[i].description || *opts[i].description != '@' )
		    if( (j=long_opt_strlen(opts+i)) > indent && j < 35 )
			 indent = j;
	}
	/* example: " -v, --verbose   Viele Sachen ausgeben" */
	indent += 10;
	if( *opts[0].description != '@' )
	    puts("Options:");
	for(i=0; opts[i].short_opt; i++ ) {
	    s = _( opts[i].description );
	    if( s && *s== '@' && !s[1] ) /* hide this line */
		continue;
	    if( s && *s == '@' ) { /* unindented comment only line */
		for(s++; *s; s++ ) {
		    if( *s == '\n' ) {
			if( s[1] )
			    putchar('\n');
		    }
		    else
			putchar(*s);
		}
		putchar('\n');
		continue;
	    }

	    j = 3;
	    if( opts[i].short_opt < 256 ) {
		printf(" -%c", opts[i].short_opt );
		if( !opts[i].long_opt ) {
		    if(s && *s == '|' ) {
			putchar(' '); j++;
			for(s++ ; *s && *s != '|'; s++, j++ )
			    putchar(*s);
			if( *s )
			    s++;
		    }
		}
	    }
	    else
		fputs("   ", stdout);
	    if( opts[i].long_opt ) {
		j += printf("%c --%s", opts[i].short_opt < 256?',':' ',
				       opts[i].long_opt );
		if(s && *s == '|' ) {
		    if( *++s != '=' ) {
			putchar(' ');
			j++;
		    }
		    for( ; *s && *s != '|'; s++, j++ )
			putchar(*s);
		    if( *s )
			s++;
		}
		fputs("   ", stdout);
		j += 3;
	    }
	    for(;j < indent; j++ )
		putchar(' ');
	    if( s ) {
		if( *s && j > indent ) {
		    putchar('\n');
		    for(j=0;j < indent; j++ )
			putchar(' ');
		}
		for(; *s; s++ ) {
		    if( *s == '\n' ) {
			if( s[1] ) {
			    putchar('\n');
			    for(j=0;j < indent; j++ )
				putchar(' ');
			}
		    }
		    else
			putchar(*s);
		}
	    }
	    putchar('\n');
	}
	if( flags & 32 )
	    puts("\n(A single dash may be used instead of the double ones)");
    }
    if( (s=strusage(19)) ) {  /* bug reports to ... */
	putchar('\n');
	fputs(s, stdout);
    }
    fflush(stdout);
    exit(0);
}

static void
show_version()
{
    const char *s;
    int i;
    /* version line */
    fputs(strusage(11), stdout);
    if( (s=strusage(12)) )
	printf(" (%s)", s );
    printf(" %s\n", strusage(13) );
    /* additional version lines */
    for(i=20; i < 30; i++ )
	if( (s=strusage(i)) )
	    printf("%s\n", s );
    /* copyright string */
    if( (s=strusage(14)) )
	printf("%s\n", s );
    /* Licence string.  */
    if( (s=strusage (10)) )
        printf("%s\n", s );
    /* copying conditions */
    if( (s=strusage(15)) )
	fputs(s, stdout);
    /* thanks */
    if( (s=strusage(18)) )
	fputs(s, stdout);
    /* additional program info */
    for(i=30; i < 40; i++ )
	if( (s=strusage(i)) )
	    fputs( (const byte*)s, stdout);
    fflush(stdout);
}


void
usage( int level )
{
    if( !level ) {
	fprintf(stderr,"%s %s; %s\n", strusage(11), strusage(13),
						     strusage(14) );
	fflush(stderr);
    }
    else if( level == 1 ) {
	fputs(strusage(40),stderr);
	exit(2);
    }
    else if( level == 2 ) {
	puts(strusage(41));
	exit(0);
    }
}

/* Level
 *     0: Copyright String auf stderr ausgeben
 *     1: Kurzusage auf stderr ausgeben und beenden
 *     2: Langusage auf stdout ausgeben und beenden
 *    10: Return license info string
 *    11: name of program
 *    12: optional name of package which includes this program.
 *    13: version  string
 *    14: copyright string
 *    15: Short copying conditions (with LFs)
 *    16: Long copying conditions (with LFs)
 *    17: Optional printable OS name
 *    18: Optional thanks list	 (with LFs)
 *    19: Bug report info
 *20..29: Additional lib version strings.
 *30..39: Additional program info (with LFs)
 *    40: short usage note (with LF)
 *    41: long usage note (with LF)
 */
const char *
default_strusage( int level )
{
    const char *p = NULL;
    switch( level ) {
      case 10: p = ("License GPLv3+: GNU GPL version 3 or later "
                    "<http://gnu.org/licenses/gpl.html>");
        break;
      case 11: p = "foo"; break;
      case 13: p = "0.0"; break;
      case 14: p = "Copyright (C) 2012 Free Software Foundation, Inc."; break;
      case 15: p =
"This is free software: you are free to change and redistribute it.\n"
"There is NO WARRANTY, to the extent permitted by law.\n";
        break;
      case 16:	p =
"This is free software; you can redistribute it and/or modify\n"
"it under the terms of the GNU General Public License as published by\n"
"the Free Software Foundation; either version 3 of the License, or\n"
"(at your option) any later version.\n\n"
"It is distributed in the hope that it will be useful,\n"
"but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
"MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n"
"GNU General Public License for more details.\n\n"
"You should have received a copy of the GNU General Public License\n"
"along with this software.  If not, see <http://www.gnu.org/licenses/>.\n";
	break;
      case 40: /* short and long usage */
      case 41: p = ""; break;
    }

    return p;
}



#ifdef TEST
static struct {
    int verbose;
    int debug;
    char *outfile;
    char *crf;
    int myopt;
    int echo;
    int a_long_one;
}opt;

int
main(int argc, char **argv)
{
    ARGPARSE_OPTS opts[] = {
    { 'v', "verbose",   0 , "Laut sein"},
    { 'e', "echo"   ,   0 , "Zeile ausgeben, damit wir sehen, was wir einegegeben haben"},
    { 'd', "debug",     0 , "Debug\nfalls mal etasws\nSchief geht"},
    { 'o', "output",    2   },
    { 'c', "cross-ref", 2|8, "cross-reference erzeugen\n" },
    { 'm', "my-option", 1|8 },
    { 500, "a-long-option", 0 },
    {0} };
    ARGPARSE_ARGS pargs = { &argc, &argv, 2|4|32 };
    int i;

    while( ArgParse( &pargs, opts) ) {
	switch( pargs.r_opt ) {
	  case -1 : printf( "arg=`%s'\n", pargs.r.ret_str); break;
	  case 'v': opt.verbose++; break;
	  case 'e': opt.echo++; break;
	  case 'd': opt.debug++; break;
	  case 'o': opt.outfile = pargs.r.ret_str; break;
	  case 'c': opt.crf = pargs.r_type? pargs.r.ret_str:"a.crf"; break;
	  case 'm': opt.myopt = pargs.r_type? pargs.r.ret_int : 1; break;
	  case 500: opt.a_long_one++;  break;
	  default : pargs.err = 1; break; /* force warning output */
	}
    }
    for(i=0; i < argc; i++ )
	printf("%3d -> (%s)\n", i, argv[i] );
    puts("Options:");
    if( opt.verbose )
	printf("  verbose=%d\n", opt.verbose );
    if( opt.debug )
	printf("  debug=%d\n", opt.debug );
    if( opt.outfile )
	printf("  outfile=`%s'\n", opt.outfile );
    if( opt.crf )
	printf("  crffile=`%s'\n", opt.crf );
    if( opt.myopt )
	printf("  myopt=%d\n", opt.myopt );
    if( opt.a_long_one )
	printf("  a-long-one=%d\n", opt.a_long_one );
    if( opt.echo       )
	printf("  echo=%d\n", opt.echo );
    return 0;
}
#endif

/**** bottom of file ****/
